In some instances of erectile impotence in which the patient does not respond to more conventional therapy, the surgical implanting of a penile prosthesis may be the only practical means of remedying the impotency.
In the past, several types of penile prostheses have been employed. One type of prosthesis consists of a pair of rods of suitable stiffness each of which is surgically implanted into a separate corpus cavernosum of the penis. One disadvantage of the rod-type implants is that the stiffness of the rods makes it difficult to implant rods of sufficient diameter so that the penis in the erectile state will have a normal girth. The sleeve prosthesis disclosed in U.S. Pat. No. 4,204,350 is an attempt to overcome that disadvantage.
Another type of penile prosthesis which is available is the inflatable prosthesis. The most common inflatable prosthesis includes two fairly long, inflatable, distensible tubes that are surgically implanted in the corpora cavernosa of the penis. Each of the tubes is connected by tubing to a pressure bulb for inflating fluid which is implanted in the scrotal sac and a large reservoir which must be implanted in the abdominal cavity. The distensible tubes are collapsible so that they can be easily implanted and they can be inflated to increase the length and girth of the penis to approach that attained in a normal erection. The prosthesis of U.S. Pat. No. 3,954,102 is representative of this type of inflatable prosthesis.
Another type of inflatable penile prosthesis that can result in increased length and girth is the type shown in U.S. Pat. Nos. 4,009,711 and 4,201,202. It basically consists of two implants each having its own relatively large, pressurizing bulb which is surgically implanted in the scrotal sac. Each implant includes a non-distensible stem made of a relatively stiff material to support the implant and an integral, collapsible, balloon-like portion which is implanted into the corpora of the pendulous penis and inflated with a pressure bulb to affect an erection.
The recently issued Hakky U.S. Pat. No. 4,718,410 discloses a similar prosthesis which consists of two implants each with its own inflatable pressure chamber which serves as a hinge. In one embodiment, the pressure chambers are surrounded by a non-distensible bellows which permits the chamber to expand longitudinally and prevents it from expanding radially.
Recently, inflatable penile prostheses have become commercially available which like the rod-type can be implanted completely in the penis. These prostheses basically consist of a pair of cylindrical implants each containing its own pump, reservoir and pressure chamber. The pressure chambers are non-distensible so that only small amounts of fluid are needed to be transferred from the reservoirs to make them rigid. These prostheses provide many advantages, but they do not significantly increase the size of the penis. Representative of such prostheses are those shown in U.S. Pats. Nos. 4,353,360 and 4,590,927.
A need still exists for a penile prosthesis which is more natural appearing in both the flaccid and erectile states.